In certain medical apparatus, such as x-ray, dental or ophthalmological apparatus, it is desireable to be able to expediently select various "functions", such as the positions of adjustable elements and the operating values thereof, with the assistance of electrical actuating devices. Previously, a plurality of hand and foot switches were arranged at different locations of the apparatus, and had to be individually actuated for selecting each of these "functions".
For example, in a dental apparatus it is important to select a variety of functions during the course of treating a patient, and to vary the position and operating values of elements contained in the apparatus. Such elements can include a patient chair, various instruments used by a physician or assistant, and auxiliary functions of the instruments. The functions of the elements to be selected or triggered can be divided into device functions, instrument functions, and auxiliary functions.
For example, device functions can include moving a physician's and/or assistant's instrument from a starting position into a working position and back to the starting position, bringing the entire patient chair, or parts thereof, such as a back rest, seat or head support, from a starting position into one or more working positions back to the starting position, and bringing the patient chair, or parts thereof, from a first working position into a second working position, such as an expectoration position, and from the second working position back to the first working position during treatment of a patient.
In known devices, the selection of device functions ensues by actuating appropriate switch elements, with which allocated electrical and/or hydraulic motor operators are actuated. The switch elements are usually manually actuated, and a few are actuated with a foot switch.
In addition, the instrument functions can include speed control of an instrument drive motor, such as an electric air motor or turbine, defining the rotational sense of the drive motor as clockwise or counter clockwise, defining and connecting cooling agents, such as air, water, or spray, preselecting the power of the instrument drive, and preselecting the type of control of the instrument drive, such as an on/off function or regulating function.
In known devices, the selection of the instrument functions ensue with switch or control elements arranged at a suitable location, by which the drives are directly or indirectly switched by valves, relays or the like.
Further, auxiliary functions can include actuating a drinking glass filling element of an assistant's instrument, actuating an expectorant basin, rinsing an assistant's instrument, actuating a call system, and actuating a door opener or the like.
Previously, the selection of auxiliary functions ensued by separate, manually actuatable switches, or buttons, arranged at different locations on the apparatus.
For purposes of simplification, the means for driving the different functions, such as motor operators, valves, relays, switch elements, power control parts, etc., are hereinafter generally referred to with the term "actuating".
Previously, a multitude of functions could only be selected (if they could be selected at all), by a multitude of actuation devices, arranged at different locations of a dental apparatus. With the exception of a few functions that were capable of being selected with foot switches, the selection of the most functions was usually accomplished manually.
However, the ever-increasing number of adjustable functions in medical apparatus has given rise to increasing problems in instrument manipulation, as well as in maintaining acceptable levels of hygiene, in apparatus requiring manual actuation to select various functions.
Recent attempts to solve this problem include the disclosure of a dental apparatus wherein a plurality of switch functions can be arranged on one or on a number of foot switches, having a corresponding plurality of actuation devices, such that the actuation devices are actuatable in different directions. However, overloading a foot switch with actuation elements in this way causes the foot switch to become unsurveyable and very difficult to operate.
Another attempt to solve this problem is disclosed in WO 89.05613, in which the execution both of instrument functions and auxiliary functions of a dental apparatus can be controlled and displayed at a display screen with the assistance of a microprocessor. To this end, the microprocessor is connected to a control and display unit that includes a plurality of function display fields, such that instrument and auxiliary functions can be selected and displayed. The apparatus also contains a switch that responds when a particular instrument is removed or replaced, such that switching can be undertaken from a first mode, in which the instrument is removed from its holder and only auxiliary functions associated with the particular instrument can be selected, to a second mode, upon returning all instruments to their holders or home positions, wherein instrument and/or auxiliary functions can be selected. The functions are contained in a hierarchically divided menu system that contains an overriding main menu, and one or more subsidiary instrument menus, having adjustment and regulating menus coupled thereto. The menus can be manually selected with the assistance of selection means in the form of an infrared light barrier that is allocated to every function display field.
When an instrument is removed from its holder, the deposited or removed condition of the instruments is determined with detectors, and a switch from "auxiliary function" mode to "instrument function" mode ensues. Within the selected mode, the foot switch then assumes a control function.